With a light weight, impact resistance, wear-resistant, corrosion-resistant, anti-UV, anti-aging, low coefficient of friction, non-toxic, non-polluting, difficult to adhere to the foreign body can absorb shock impact and excellent anti-noise performance, instead of just copper the best material of a metallic material such as aluminum. Variety of products made of this material, the case does not change the size of the original design directly instead of metal products. Performance to meet the requirements of strength, stiffness, resistance to fatigue.